Re: [fpc-pascal] Directory Tree
Le 18/04/2021 à 16:10, James Richters via fpc-pascal a écrit : RE: [fpc-pascal] Directory Tree I getuFileVirtualTree.pas(533,9) Error: identifier idents no member "DefaultEncoding" It seems, using svn blame, that DefaultEncoding has been added in FreePascal source trunk on the svn server on June 4th 2019. I don't know the version number of the fpc release following this date but it's likely your lazarus/freepascal is older than mine. I use currently Lazarus 2.0.12 / fpc 3.2.0. It has the incorrect character in front of File1, It’s a vertical_line_char instead of a crossing_char. I have corrected this point, it should work now. ___ fpc-pascal maillist - fpc-pascal@lists.freepascal.org https://lists.freepascal.org/cgi-bin/mailman/listinfo/fpc-pascal
Re: [fpc-pascal] Directory Tree
Indeed, I think it's difficult (if possible) to change the behaviour of the multiselection this way. The TTreeview.MultiSelectStyle property allows you to change from CtrL+Click to Shift+Click. https://lazarus-ccr.sourceforge.io/docs/lcl/comctrls/tmultiselectstyle.html To make the multi selection with just a left click, I think the best way would be to use the TVirtualTreeView with checkboxes. ___ fpc-pascal maillist - fpc-pascal@lists.freepascal.org https://lists.freepascal.org/cgi-bin/mailman/listinfo/fpc-pascal
Re: [fpc-pascal] Directory Tree
If you just select files, as Bart stated in another message, I think TShellTreeView will be more adequate and easier than TTreeView (actually TShellTreeView is a file tree specific descendent TTreeView). In TTreeView (and TShellTreeView) you can enable multiselection by adding tvoAllowMultiSelect in Options set (something like "with TreeView1 do Options:=Options+[tvoAllowMultiSelect];" or better by just checking Options/tvoAllowMultiSelect in the Object inspector) https://wiki.freepascal.org/TTreeView#Example_of_using_Multiple_Node_Selection_for_Multiple_User_Selections If you want checkboxes, I think it's possible with TVirtualStringTree from the VirtualTreeView package, it may be a bit harder to implement (as far as I remember you need your own data structure to store the status of the tree) : https://wiki.freepascal.org/VirtualTreeview https://wiki.freepascal.org/VirtualTreeview_Example_for_Lazarus#Checkbox VirtualTreeView package is included in Lazarus v2.0+, but I'm not sure it's installed by default: if you don't find a tab "Virtual controls" in your components, you may need to go to Package menu/Install packages, select virtualtreeview_package 5.5.3.1 for installation and rebuild Lazarus. Here you should enable multiselection with something like with VirtualStringTree1.TreeOptions do SelectionOptions:=SelectionOptions+[toMultiSelect]; or by checking TreeOptions/SelectionOptions/toMultiSelect in the Object inspector when your VirtualStringTree1 is selected. (I've used VirtualTreeView a while ago, I didn't test checkboxes today) ___ fpc-pascal maillist - fpc-pascal@lists.freepascal.org https://lists.freepascal.org/cgi-bin/mailman/listinfo/fpc-pascal
Re: [fpc-pascal] Directory Tree
TStringList works pretty much like an inifile section. The index corresponds to the line number in you text block. The Names property corresponds to the part of the line before the '=' char. The ValueFromIndex property corresponds to the part of the line after the '=' char. So if you line i contains "M:\Project1\File1=8:32", Names[i] will returns "M:\Project1\File1" and ValueFromIndex returns "8:32" The text block (property Text) is viewed like a kind of list of virtual records "name=value" You can iterate the nodes in the TreeView and change their text. I have updated the example with a VirtualTreeView on a new form (you should download all the files in a different directory). It's more complex to implement, but with checkboxes you just need a simple click. ___ fpc-pascal maillist - fpc-pascal@lists.freepascal.org https://lists.freepascal.org/cgi-bin/mailman/listinfo/fpc-pascal
Re: [fpc-pascal] Directory Tree
I have updated the VirtualTreeView example with sub-totals of time. ___ fpc-pascal maillist - fpc-pascal@lists.freepascal.org https://lists.freepascal.org/cgi-bin/mailman/listinfo/fpc-pascal
Re: [fpc-pascal] Directory Tree
Le 22/04/2021 à 23:17, James Richters via fpc-pascal a écrit : For some reason the ODT file wants to know if I want to translate it from French, and while the font is “Courier New” for anything I would type into the document, the font of the text itself is “Liberation Serif” If I change the font manually to “Courier New” I get gaps in the vertical lines,but if I change it to “Consolas” there are no gaps and it looks perfect. Basically, I think you should replace the FileVirtualTree_txt_to_odt.odt by one created on your machine. Just create an empty document in Word and save it in odt format as FileVirtualTree_txt_to_odt.odt. To change the font, don't modify it directly in the paragraph, but modify the default style, change the font of the default style to the one which fits the best for you. Eventually, you could make a style with a specific name, and specify it in the pascal code. I have changed the font of the default style to Consolas. It works on my Windows machine, but not on Ubuntu. I have switched the language to English US too. So I thought I should be able to just save a template with the font set to “Consolas” and the spacing set to “No Spacing” which is basically single spacing it.. Well when I save it like that, when I try to run it I get: Unable to Open File: C:\Users\James\AppData\Local\Temp\Fi8004.odt Press OK and risk data corruption or press abort to kill the program I think it must have something to do with using Microsoft Word to save the template. May be the file was already opened ? or the template broken ? (saved in docx format instead of odt ?) ___ fpc-pascal maillist - fpc-pascal@lists.freepascal.org https://lists.freepascal.org/cgi-bin/mailman/listinfo/fpc-pascal
Re: [fpc-pascal] Directory Tree
Le 22/04/2021 à 22:17, James Richters via fpc-pascal a écrit :
RE: [fpc-pascal] Directory Tree
My system could not find DejaVuSans,
You can find it in
C:\lazarus\fpc\3.2.0\source\packages\fcl-report\demos\fonts.
May be you don't need to install the font, just add on the line below
where you changed the font:
gTTFontCache.SearchPath.Add('C:\lazarus\fpc\3.2.0\source\packages\fcl-report\demos\fonts\');
but I found it in the code and changed it to Consolas which is always
included with Windows and is a nice clear monospaced font with nice
box characters.
Notice it shouldn't be the name displayed for the font by Windows, but
its Postscript name, which is buried somewhere in the ttf file, for
example CourierNewPSMT for Courier New.
It’s almost perfectthe only issue is that there is too much space
between the lines, so the verticals don’t touch the way they are
supposed it.. it’s not quite double spaced, more like 1-1/4 or 1-3/8
spaced.. if it was single spaced it would be perfect.I don’t know how
to control the spacing between lines.I made the font bigger but there
was still a gap.If I could close that gap it would be perfect.
Is there an easy way to send a page break between the file list and
the tree?
I'm not an expert of fcl-report but allowing to Michael Van Canneyt
response to "fpreport: can not use two ObjectLists as datasource in one
report" on 18/03/2021, I think this would be difficult. It think it
would need 2 distinct databands which seems to be not possible.
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Re: [fpc-pascal] Hello, new Pascal programmer. had a question!
May be something like "Snap!" ? https://snap.berkeley.edu/snap/snap.html#present:Username=trev1315=plane%202 https://snap.berkeley.edu/project?user=trev1315=plane%202 On my own, I think starting with Lazarus and GUI apps would be far easier. If you create a new app from a template, you can get a running app nearly without typing anything. ___ fpc-pascal maillist - fpc-pascal@lists.freepascal.org https://lists.freepascal.org/cgi-bin/mailman/listinfo/fpc-pascal
Re: [fpc-pascal] Hello, new Pascal programmer. had a question!
I've forgotten to add the link to "Snap!" manual: https://snap.berkeley.edu/snap/help/SnapManual.pdf ___ fpc-pascal maillist - fpc-pascal@lists.freepascal.org https://lists.freepascal.org/cgi-bin/mailman/listinfo/fpc-pascal
Re: [fpc-pascal] Explicit Interface implementation and inheritance
Ooops, may be I hit reply too fast.
It looks like when you write " TObjB = class(TObjA, IBBB)" you just
implement IAAA twice.
If you comment out IBBB
TImpB = class(TImpA{, IBBB})
public
procedure CallOfB;
//procedure IBBB.MethodB = CallOfB;
end;
then the "No matching implementation" error disappears, the inherited
implementation is well taken in account.
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Re: [fpc-pascal] Explicit Interface implementation and inheritance
Le 15/08/2021 à 00:43, Dmitry Boyarintsev via fpc-pascal a écrit : Why is interface implementation not inherited, if explicit implementation is used. I guess this is because you can implement an interface through delegation too: https://www.freepascal.org/docs-html/ref/refse48.html type IMyInterface = interface procedure P1; end; TMyClass = class(TInterfacedObject, IMyInterface) private FMyInterface: IMyInterface; // interface type public property MyInterface: IMyInterface read FMyInterface implements IMyInterface; end; ___ fpc-pascal maillist - fpc-pascal@lists.freepascal.org https://lists.freepascal.org/cgi-bin/mailman/listinfo/fpc-pascal
Re: [fpc-pascal] Conversion from C to Pascal - Left bit shift
I made a few tests on Ubuntu 64 bits (arch x86_64) with variations on a small test program: var E2: Byte= 3; E1: LongWord= 1; E: QWord; begin E:= (1000*E1) shl E2; writeln( 'E2', E2); writeln( 'E1', E1); writeln( 'E', E); end. In the assembly window, shl is computed on 64 bits %rax, I get : project1.lpr:132 E:= (1000*E1) shl E2; 004011B2 8b05d8f50c00 mov 0xcf5d8(%rip),%eax # 0x4d0790 004011B8 4869c0e803 imul $0x3e8,%rax,%rax 004011BF 0fb60dbaf50c00 movzbl 0xcf5ba(%rip),%ecx # 0x4d0780 004011C6 48d3e0 shl %cl,%rax 004011C9 48890580b51000 mov %rax,0x10b580(%rip) # 0x50c750 Changing the formula to E:= E1 shl E2, shl computed on 32 bits %edx, (I don't understand the "and %edx,%edx", may be just to clear the carry ?) I get : project1.lpr:132 E:= E1 shl E2; 004011B2 0fb605c7f50c00 movzbl 0xcf5c7(%rip),%eax # 0x4d0780 004011B9 8b15d1f50c00 mov 0xcf5d1(%rip),%edx # 0x4d0790 004011BF 89c1 mov %eax,%ecx 004011C1 d3e2 shl %cl,%edx 004011C3 21d2 and %edx,%edx 004011C5 48891584b51000 mov %rdx,0x10b584(%rip) # 0x50c750 Changing E1 to QWord ( E1: QWord= 1; ), shl is computed on 64 bits %rax, I get : project1.lpr:132 E:= E1 shl E2; 004011B2 0fb605c7f50c00 movzbl 0xcf5c7(%rip),%eax # 0x4d0780 004011B9 488b15d0f50c00 mov 0xcf5d0(%rip),%rdx # 0x4d0790 004011C0 4889c1 mov %rax,%rcx 004011C3 48d3e2 shl %cl,%rdx 004011C6 48891583b51000 mov %rdx,0x10b583(%rip) # 0x50c750 ___ fpc-pascal maillist - fpc-pascal@lists.freepascal.org https://lists.freepascal.org/cgi-bin/mailman/listinfo/fpc-pascal
Re: [fpc-pascal] My Linux service application consumes 10% CPU when idling - why?
I don't know if it's related, but I experienced a similar problem a few years ago. It's a console dll written in Freepascal and compiled for Win64 and Linux (Ubuntu). It uses several threads and uses CheckSynchronize to make calls in the main thread. The dll is loaded and used by a 4gl program (www.4js.com), I think the 4gl runtime is compiled with Visual C++ on Windows and GNU C++ on Linux. With recent (a few years ago) Freepascal a similar CPU consumption when idle appeared, but only in Windows, not in Linux. I didn't needed recent functionalities of Freepascal, so a dirty workaround for me for this project was to stick to Lazarus 1.6 / 2016 02 14 / FPC 3.0.0 / SVN 51360 (from menu Help/About Lazarus). I don't have the CPU consumption with this version. ___ fpc-pascal maillist - fpc-pascal@lists.freepascal.org https://lists.freepascal.org/cgi-bin/mailman/listinfo/fpc-pascal
Re: [fpc-pascal] FPC and WebAssembly
Wonderful ! Thank you very much for all your work and all the work of the FPC / Lazarus team ! And Merry Christmas for all ! ___ fpc-pascal maillist - fpc-pascal@lists.freepascal.org https://lists.freepascal.org/cgi-bin/mailman/listinfo/fpc-pascal
Re: [fpc-pascal] BoolToStr
Le 29/08/2022 à 01:41, James Richters via fpc-pascal a écrit : If a special function is needed for some COM thing or weird Winapi thing, then that function should be part of the unit that needs it, not modifying the generic function intended to be used for general purpose applications output something that does not conform to other Pascal Boolean datatypes and just confuses everyone. Unfortunately, it's not just a few windows functions which use this behaviour but the whole Windows API: https://docs.microsoft.com/fr-fr/windows/win32/api/winuser/nf-winuser-getmessage?redirectedfrom=MSDN The Microsoft BOOL datatype uses this convention so the whole ecosystem is attracted to use it (other C program on windows, Delphi, ... ) I imagine it's more efficient at the assembler level to process the result of functions returning boolean. ___ fpc-pascal maillist - fpc-pascal@lists.freepascal.org https://lists.freepascal.org/cgi-bin/mailman/listinfo/fpc-pascal
Re: [fpc-pascal] I am offering a $100 reward for linking static libraries
Le 01/09/2022 à 07:50, Michael Van Canneyt via fpc-pascal a écrit : The file seems corrupt. I tried several programs, none managed to open it. Indeed more than corrupt. For me, file is just empty (size 0 byte) ___ fpc-pascal maillist - fpc-pascal@lists.freepascal.org https://lists.freepascal.org/cgi-bin/mailman/listinfo/fpc-pascal
Re: [fpc-pascal] MQTT package for freepascal/lazarus?
Le 22/10/2022 à 23:37, Bo Berglund via fpc-pascal a écrit : If I could get at each output that mosquitto_cli writes into a script or such then I would be good to go. Maybe with a redirection ( > ) to a file in bash ? ___ fpc-pascal maillist - fpc-pascal@lists.freepascal.org https://lists.freepascal.org/cgi-bin/mailman/listinfo/fpc-pascal
Re: [fpc-pascal] Calculating CRC16?
I couldn't verify the code but it should be relatively close to your c++ example. Not sure of the width of int type, I supposed it's 16 bits wide: function CRC16( crc: Word; buf: PByte; len: Word; Poly:Word=$A001): Word; var pos: Word; i: Word; begin for pos:= 0 to len-1 do begin crc:= crc xor Word(buf[pos]); // * XOR byte into least sig. byte of crc // * Loop over each bit for i:= 8 downto 1 do begin // * If the LSB is set if ((crc and $0001) <> 0) then begin // * Shift right and XOR 0xA001 crc:= crc shr 1; crc:= crc xor Poly; end // * Else LSB is not set else // * Just shift right crc:= crc shr 1; end; end; Result:= crc; end; var S: String; begin Readln( S); WriteLn( IntToHex( CRC16( 0, PByte(@S[1]), Length(S), $8005), 4)); end. ___ fpc-pascal maillist - fpc-pascal@lists.freepascal.org https://lists.freepascal.org/cgi-bin/mailman/listinfo/fpc-pascal
Re: [fpc-pascal] MQTT package for freepascal/lazarus?
Le 23/10/2022 à 23:59, Bo Berglund via fpc-pascal a écrit : Might get stuck at readln(s) if no messages are sent, i.e. no carriage-return coming along? AFAIK readln is blocking, right? I've made a test with mosquitto_pub, it seems there is a line ending at the end of each message, so you will be blocked only when there are no new message available. If your program needs to do something else during the wait for a new message, you'll need to dedicate a thread or a separate program. Maybe dedicate a thread, putting your Readln (in the case of mosquitto_sub ... |SomePascalProgram) or the loop (in the case of use of TProcess) in your TThread descendant Execute method. There you when you receive a new mqtt message you can call TThread.Synchronize (on a method of your forms for example) to process the message in your main thread. ___ fpc-pascal maillist - fpc-pascal@lists.freepascal.org https://lists.freepascal.org/cgi-bin/mailman/listinfo/fpc-pascal
Re: [fpc-pascal] MQTT package for freepascal/lazarus?
If your main program is a console program, it's likely that you'll need to call CheckSynchronize( from unit Class) in your main program/main thread from time to time in order to allow the execution of calls of methods specified in Synchronize in your thread (which reads mqtt messages). I'm not 100% sure for recent freepascal, but I needed to do this in a pascal dll (with threads) called by a C++ program, the all running in console. ___ fpc-pascal maillist - fpc-pascal@lists.freepascal.org https://lists.freepascal.org/cgi-bin/mailman/listinfo/fpc-pascal
Re: [fpc-pascal] MQTT package for freepascal/lazarus?
May be with a pipe | ? Something like mosquitto_sub -h 192.168.117.131 -F '@Y-@m-@d @H:@M:@S ; %t ; %p' -t '#' | SomePascalProgram This way you'll receive the output of mosquitto_sub on the standard input of SomePascalProgram. I've tested locally on an Apache log with tail -f /var/log.apache2/access.log | grep http Le 23/10/2022 à 15:31, Bo Berglund via fpc-pascal a écrit : What happens if the data in the AProcess output stream is less than my buffer size, will it then stall until as many messages have arrived as will fill the buffer? I think you can useAProcess.Output.NumBytesAvailable to avoid stalling and read just what is available : https://www.freepascal.org/docs-html/fcl/pipes/tinputpipestream.numbytesavailable.html ___ fpc-pascal maillist - fpc-pascal@lists.freepascal.org https://lists.freepascal.org/cgi-bin/mailman/listinfo/fpc-pascal
Re: [fpc-pascal] MQTT package for freepascal/lazarus?
Le 23/10/2022 à 22:50, Jean SUZINEAU via fpc-pascal a écrit : This way you'll receive the output of mosquitto_sub on the standard input of SomePascalProgram. A very small example for SomePascalProgram for use with pipe, reading on standard input and writing on standard output : var s: String; begin repeat readln( s); writeln( s); until false; end. ___ fpc-pascal maillist - fpc-pascal@lists.freepascal.org https://lists.freepascal.org/cgi-bin/mailman/listinfo/fpc-pascal
Re: [fpc-pascal] mciSendString with long file names
May be by escaping the spaces with ^ ? Something like: MyFileName:= StringReplace(MyFileName, ' ', '^ ', [rfReplaceAll]); ^ is the escape char for cmd.exe but may be it is active in this context too ? Le 20/09/2022 à 18:31, James Richters via fpc-pascal a écrit : I just tried it that way: Var pcmd: String; MyFileName: String; pcmd:='play "'+MyFileName+'"'+#0; mciSendString(@pcmd[1],Nil,0,0); ___ fpc-pascal maillist - fpc-pascal@lists.freepascal.org https://lists.freepascal.org/cgi-bin/mailman/listinfo/fpc-pascal
Re: [fpc-pascal] Get highest element of a StringList
As Bart suggested, you can use too the for/in loop: for s in sl do
WriteLn( s);
For example:
var
sl: TStringList;
s: String;
begin
sl:= TStringList.Create;
try
sl.Add('1');
sl.Add('2');
for s in sl do WriteLn( s);
finally
FreeAndNil( sl);
end;
end.
Output:
1
2
This works on arrays and strings too.
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Re: [fpc-pascal] Union field after property violates "field before property" rule + property of union field not possible.
May the solution to your problem should be just : TDataExample = record case integer of 0: (mData: Int64); 1: (mByte: packed array[0..7] of Byte); 2: (UnionField: Int64); end; ? You aren't going to define a getter or setter method on your property, just an "alias" to mData ? ___ fpc-pascal maillist - fpc-pascal@lists.freepascal.org https://lists.freepascal.org/cgi-bin/mailman/listinfo/fpc-pascal
Re: [fpc-pascal] Union field after property violates "field before property" rule + property of union field not possible.
For this particular error I think you should just follow the advice of compiler in the error message : Le 14/08/2022 à 11:49, Skybuck Flying via fpc-pascal a écrit : // normal/standard property property StandardField : integer read mStandardField write mStandardField; mStandardField : integer; // ERROR "field definition not allowed after methods or properties" problem 2. Error: Fields cannot appear after a method or property definition, start a new visibility section first property StandardField : integer read mStandardField write mStandardField; public mStandardField : integer; But I think you'll get then, on the property line : Error: Unknown class field or method identifier "mStandardField" ___ fpc-pascal maillist - fpc-pascal@lists.freepascal.org https://lists.freepascal.org/cgi-bin/mailman/listinfo/fpc-pascal
Re: [fpc-pascal] Union field after property violates "field before property" rule + property of union field not possible.
An if you eventually need a read only UnionField : TmByte= packed array[0..7] of Byte; TDataExample2 = record internal : record case integer of 0: (mData: Int64); 1: (mByte: TmByte); end; property mByte : TmByte read internal.mByte; property UnionField: Int64 read internal.mData; end; ___ fpc-pascal maillist - fpc-pascal@lists.freepascal.org https://lists.freepascal.org/cgi-bin/mailman/listinfo/fpc-pascal
Re: [fpc-pascal] Why does RunCommand not produce the correct output?
Le 01/05/2023 à 17:00, Bo Berglund via fpc-pascal a écrit :
I have created a shellscript with the same command string
May be running directly your script in bash:
RunCommand('/bin/bash', ['your_script.sh' ], OutData)
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Re: [fpc-pascal] Why does RunCommand not produce the correct output?
I don't have an example at hand but I think you should run a bash
interpreter, something like :
RunCommand('/bin/bash', ['-c', ListCmd], OutData)
but I'm not 100% sure.
There is a good documentation at:
https://wiki.freepascal.org/Executing_External_Programs
May be you need to split your command in several calls and use
AProcess.Options := [poUsePipes];
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Re: [fpc-pascal] Pause Key
... I wouldn't be surprised that James's program is a console one, not using TForm nor any windows message loop to process WM_ messages, but I may be wrong. It can be more tricky in this case. ___ fpc-pascal maillist - fpc-pascal@lists.freepascal.org https://lists.freepascal.org/cgi-bin/mailman/listinfo/fpc-pascal
Re: [fpc-pascal] FPC/Lazarus on RPi4 - How to read/write I2C connected EEPROM?
May be you could get the source code of i2ctransfer from i2c-tools and compare it with the code in i2c.pas ? ___ fpc-pascal maillist - fpc-pascal@lists.freepascal.org https://lists.freepascal.org/cgi-bin/mailman/listinfo/fpc-pascal
Re: [fpc-pascal] fpc isn't optimised for tail recursion, is it?
Le 12/06/2023 à 19:05, Steve Litt via fpc-pascal a écrit : Busted! I used Pascal 1984-1993 So I guess you are not familiar too with the "Result" variable which appeared with Delphi 1 in 1995 if I remember correctly. nextt:= num; can be written to as : Result:= num; https://www.freepascal.org/docs-html/ref/refse94.html I prefer Result because it reduces risks of confusion with recursive call and you can eventually take the address of Result with @Result (where @nextt would take the address of the function nextt), pass it by reference to another function ( e.g. FillChar( Result, SizeOf(Result), 0); ) , it behaves like a normal variable.___ fpc-pascal maillist - fpc-pascal@lists.freepascal.org https://lists.freepascal.org/cgi-bin/mailman/listinfo/fpc-pascal
Re: [fpc-pascal] Function to create a record ?
Hello, I have a hard time trying to understand what you want to test.
In your functions, you are using a record, not a class or a pointer to
record or an object.
The personrecord just behave in your parameters and return value as an
Integer or a String, and your fillchar doesn't write outside of the
memory allocated for you junkvar, so I don't see what can go wrong.
If you trace the address of person.name like this:
//begin code
begin
person := newperson();
writeln('1, person.name address: ',
IntToHex(Int64(Pointer(@(person.name);
fillchar(junkvar, junkvar_size, 'a');
person2 := newperson();
fillchar(junkvar, junkvar_size, 'b');
person := modperson(person, 'Martin');
person := modperson(person2, 'Maria');
writeln('2, person.name address: ',
IntToHex(Int64(Pointer(@(person.name);
{writeln(junkvar);}
writeperson(person);
writeperson(person2);
end.
//end code
You'll see that the address doesn't change, for example:
1, person.name address: 0050C7F0
2, person.name address: 0050C7F0
But if you declare your personrecord as a class, the things doesn't
behave the same way:
//begin code
const
junkvar_size = 2000;
type
personclass = class
name: string;
end;
var
person: personclass;
person2: personclass;
junkvar: array[1..junkvar_size] of char;
function newperson(): personclass;
var newp: personclass;
begin
newp:= personclass.Create;
newp.name := '';
newperson := newp;
end;
function modperson(person: personclass; name: string): personclass;
begin
person.name := name;
modperson := person;
end;
procedure writeperson(person: personclass);
begin
writeln(person.name);
end;
begin
person := newperson();
writeln('1, person.name address: ',
IntToHex(Int64(Pointer(@(person.name);
fillchar(junkvar, junkvar_size, 'a');
person2 := newperson();
fillchar(junkvar, junkvar_size, 'b');
person := modperson(person, 'Martin');
person := modperson(person2, 'Maria');
writeln('2, person.name address: ',
IntToHex(Int64(Pointer(@(person.name);
{writeln(junkvar);}
writeperson(person);
writeperson(person2);
end.
//end code
You'll get a different address, something like:
1, person.name address: 77F910E8
2, person.name address: 77F91108
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Re: [fpc-pascal] Function to create a record ?
Oops, I hit "Send message" too quickly. The only difference in the second code is: - personrecord renamed to personclass and declared as "personclass = class" - "newp:= personclass.Create;" added in function newperson Of course for a clean code, you'll need to call something like "FreeAndNil( person);" or "person.free" to release properly the memory allocated. ___ fpc-pascal maillist - fpc-pascal@lists.freepascal.org https://lists.freepascal.org/cgi-bin/mailman/listinfo/fpc-pascal
Re: [fpc-pascal] fpc isn't optimised for tail recursion, is it?
According to you other posts, I won't be surprised that you think in a C/C++ way. This doesn't change anything in your last example, but particularly : nextt := num; doesn't behave like in C : return num; In pascal I think the equivalent would be : nextt := num; exit; ___ fpc-pascal maillist - fpc-pascal@lists.freepascal.org https://lists.freepascal.org/cgi-bin/mailman/listinfo/fpc-pascal
Re: [fpc-pascal] Legitimate use of for and break
Le 17/06/2023 à 20:07, Travis Siegel via fpc-pascal a écrit : Is this a relatively new addition to fpc or something? I 've just found it in my Delphi 7 code (and code very likely written for Delphi 4), so I think it's there since at least 2000-2001 ... May be it appeared with Delphi 1 ? ___ fpc-pascal maillist - fpc-pascal@lists.freepascal.org https://lists.freepascal.org/cgi-bin/mailman/listinfo/fpc-pascal
Re: [fpc-pascal] Microsoft SAPI on Freepascal
It sounds like "SpVoice := CreateOleObject('SAPI.SpVoice');" is failing
and then SpVoice is nil ?
May be try with an OleVariant instead of a simple Variant ? (i.e declare
var SpVoice: OleVariant; )
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Re: [fpc-pascal] Floating point question
I've just made a small test with the old Borland Delphi 7.0 build 4453 from 2002 : ... type TForm1 = class(TForm) m: TMemo; procedure FormCreate(Sender: TObject); end; ... procedure TForm1.FormCreate(Sender: TObject); var GG: Extended; S: String; begin GG := 8427+33/1440.0; Str( GG: 20 : 20, S); m.Lines.Add( 'GG = '+S); end; I get : GG = 8427.02291700 But I'm cautious, it's a delphi 7 running on a broken installation of Wine on Ubuntu 22.04, I had to modify an existing delphi 7 project for this test, I couldn't save a new project because of problems with wine. I have an old astronomical made with delphi 7 that I've written around 2000, and I ported a part of it to Freepascal, I'm nearly sure there are unnoticed errors in this freepascal port due to to this behaviour ... (Not really a problem because the program isn't sold any more, but I'll have a look next time I compile it) ___ fpc-pascal maillist - fpc-pascal@lists.freepascal.org https://lists.freepascal.org/cgi-bin/mailman/listinfo/fpc-pascal
Re: [fpc-pascal] Floating point question
Le 09/02/2024 à 20:53, Jonas Maebe via fpc-pascal a écrit : However, adding support for an option called -CFMax or similar should be no problem. It would be very nice to compile old code ___ fpc-pascal maillist - fpc-pascal@lists.freepascal.org https://lists.freepascal.org/cgi-bin/mailman/listinfo/fpc-pascal
Re: [fpc-pascal] Labels
Le 17/12/2023 à 17:47, Adriaan van Os via fpc-pascal a écrit :
Turbo Pascal (5.5) defines
label = digit-sequence .
Are you sure ?
I had a doubt and I had a look in some very old source code from 1990
made with tp 5.5, it seems you could have letters in labels.
Excerpt of the code:
PROCEDURE EntCh(var col,lin,lmax:byte;var nbre:boolean;var ch:string);
{entr‚e d'une chaŒne de longueur maxi lmax, si nbre=true, on ne peut entrer}
{que des nombres, signes - et + et point d‚cimal }
LABEL e00,e01,e02,e03,e04;
VAR q,cpos,i,v:byte;
k :char;
BEGIN e00:ch:='';
q :=0;
cpos:=col;
gotoXY(col,lin);
textbackground(7);textcolor(0);
for i:=1 to lmax do write('_');
gotoXY(col,lin);goto e02;
e01:bip;
e02:k:=readkey;v:=ord(k);
if ((q>0) and (v=8)) then
begin
cpos:=cpos-1;q:=q-1;
gotoXY(cpos,lin);write('_');
ch:=left(ch,length(ch)-1);
gotoXY(cpos,lin);
goto e02;
end;
if ((q=0) and (v=13)) then
begin
ch:=k;goto e04;
end;
if (v=13) then goto e04;
case nbre of
true : if ((v>47)and (v<58)) or (v=46) then
goto e03 else goto e01;
false: if (v>31) then goto e03 else goto e01;
end; {case nbre of}
e03:q:=q+1;if (q>lmax) then goto e01;
write(k);ch:=ch+k;cpos:=cpos+1;goto e02;
e04:textbackground(0);textcolor(7);
gotoXY(col,lin);write(ch);write(space(lmax-length(ch)));
END; {procedure EntCh(...)}
{--}
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Re: [fpc-pascal] case statement
Le 15/12/2023 à 10:39, Adriaan van Os via fpc-pascal a écrit : I don't see a semicolon in the formal syntax. May be included in the ' "DO" statement ' ? ___ fpc-pascal maillist - fpc-pascal@lists.freepascal.org https://lists.freepascal.org/cgi-bin/mailman/listinfo/fpc-pascal
Re: [fpc-pascal] What's in Hello World
Le 08/01/2024 à 13:51, Peter B via fpc-pascal a écrit : or if not, is there another way to turn it on in the textmode IDE? No idea. Its easy enough if you compile from the command line. fpc -Os -XX hello.pas If stripping is not on by default, also use -Xs I guess that in the textmode IDE you just have to go Options/Compiler and in the bottom in "Additional compiler args" you just have to add -Os -XX - Xs -Os : Optimize for size rather than speed -Xs : Strip all symbols from executable -XX : Try to smartlink units (defines FPC_LINK_SMART) ___ fpc-pascal maillist - fpc-pascal@lists.freepascal.org https://lists.freepascal.org/cgi-bin/mailman/listinfo/fpc-pascal
Re: [fpc-pascal] Floating point question
Le 22/02/2024 à 15:08, Thomas Kurz via fpc-pascal a écrit : But it's supported on Linux but not on Windows? Huh? As far as I know Extended is not supported on Linux.___ fpc-pascal maillist - fpc-pascal@lists.freepascal.org https://lists.freepascal.org/cgi-bin/mailman/listinfo/fpc-pascal
Re: [fpc-pascal] Floating point question
I see that Wikipedia is not very clear on this, you just find "x86" mentioned, but for Pascal: "this Extended type is available on 16, 32 and 64-bit platforms, possibly with padding" https://en.wikipedia.org/wiki/Extended_precision ___ fpc-pascal maillist - fpc-pascal@lists.freepascal.org https://lists.freepascal.org/cgi-bin/mailman/listinfo/fpc-pascal
Re: [fpc-pascal] Type-casting a class variable
I didn't tested but I imagine it could be done with something like this ? type TWindow_Class= class of TWindow; begin ... (myClass as TWindow_Class).CreateNewWindow( ); ___ fpc-pascal maillist - fpc-pascal@lists.freepascal.org https://lists.freepascal.org/cgi-bin/mailman/listinfo/fpc-pascal
